The present invention relates to a unique and novel pocket filter arrangement and a method and apparatus for making the same and, more particularly, to a pocket filter arrangement, method and apparatus for pocket shaping and restricting pocket inflation with a minimum of interference to a fluid stream to be filtered by the unique pocket filter.
Pocket filter assemblies are generally well known in the fluid filtration art. Past assembly arrangements include one or more filter cartridges or filter bags that are secured across dirty fluid streams to be treated so that particulate materials are separated from such fluid streams as they flow through the filter media of the filter bags, the bags being replaced by fresh bags whenever necessary.
In such filter arrangements, it has proven desirable to minimize interfering contact between adjacent bags, to enhance fluid flow through the filter arrangements so as to effectively utilize a maximum of fluid filtering area with a minimum of fluid flow pressure loss and with a concomitant reduction of required operating energy. In U.S. Pat. No. 4,056,375, issued to W. Ringel et al on Nov. 1, 1977, wedge-shaped, stiffened filter pockets, incorporating laminar spacing elements secured to the wedge faces of the pockets by fusion, have been utilized to separate dust particles from an air stream. The laminar spacing elements have been comparatively difficult to manufacture and assemble and have tended to interfere with air stream flow through the filtering area, limiting full use of the filtering area, with the methods of manufacture and machinery utilized being comparatively complex and unsuitable for maximizing filtration efficiency. In U.S. Pat. No. 4,356,011, issued to C. E. Day et al on Oct. 26, 1982, the filter bags disclosed include a plurality of alternating rows of filamentary stays or span stitching spaced across the filter bag width to shape the bag into a plurality of communicating tube-like sections. Such an arrangement and like arrangements also have been comparatively complex and expensive in manufacture, maintenance and operation and have tended to limit maximum usage of filtering area and also have tended to interfere with uniform fluid flow through the filtering area for the treated fluid streams. In U.S. Pat. No. 5,215,609, issued to S. L. Sanders on Jun. 1, 1993, a comparatively complex and expensive ultrasonic welding method for forming and manufacturing bag filters is disclosed with no particular consideration being given to adjacent filter bag interference and the inflation limitation of each of the filter bags.
The present invention provides a unique and novel filter bag manufacturing apparatus and method which is straightforward, economical and efficient in manufacture, assembly and maintenance, requiring a minimum of parts and a minimum of operating steps to produce a unique and novel filter bag arrangement which can efficiently and effectively filter particulate matter from a particulate laden fluid stream to be treated with a minimum of pressure drop and, thusly, with reduced energy requirements. Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.